CN117685586A - Fuel injection device, combustion chamber and aeroengine - Google Patents

Abstract

The invention provides a fuel injection device, a combustion chamber and an aeroengine, and belongs to the technical field of aeroengines. The fuel injection device is used for a combustion chamber of the aeroengine, and comprises an injection end, wherein the injection end is provided with a main fuel injection hole and a secondary fuel injection hole, the main fuel injection hole is positioned at the outer periphery side of the secondary fuel injection hole, and the injection direction of the secondary fuel injection hole is inclined towards the outer periphery side of the secondary fuel injection hole. The secondary fuel injected by the secondary injection hole is injected towards the main fuel stage backflow gas, moves to the vicinity of the ignition device along with the main fuel stage backflow gas, so that the ignition success rate of the secondary fuel is improved, meanwhile, as the secondary fuel is obliquely injected, the diffusion range of the secondary fuel is enlarged, the secondary fuel ignition boundary is widened, and the energy requirement of an ignition system is reduced.

Description

Fuel injection device, combustion chamber and aeroengine

Technical Field

The invention relates to the technical field of aeroengines, in particular to a fuel injection device, a combustion chamber and an aeroengine.

Background

At present, aviation engines, particularly aviation turbine engines mainly use aviation kerosene as fuel, wherein the aviation kerosene is a typical hydrocarbon fossil fuel with high carbon ratio, and tail gas discharged after combustion is high-altitude CO ₂ And the main sources of various types of contaminants. To reduce CO ₂ The fuel of the aero-engine starts to transition from aviation kerosene to various clean energy sources, and the most ideal clean energy source is hydrogen, so that zero carbon emission can be realized theoretically. Compared with other liquid or gaseous hydrocarbon fuels, the hydrogen has the characteristics of rich sources, light weight, high energy density, environmental protection, various storage modes and utilization modes and the like, the completely combusted product is water, and environmental pollution is not caused, but correspondingly, the hydrogen has the characteristics of strong diffusivity, inflammability, explosiveness, high storage requirement and the like on the combustion characteristic, and the characteristics are favorable for popularization and use of the hydrogen as a fuel on an aeroengine.

The fuel injection devices of existing aircraft engines are not suitable for hydrogen injection, ignition and flame stabilization. In the prior art, a fuel injection device is arranged in a combustion chamber of an aeroengine, and the fuel injection device is usually provided with a central staged injection, namely a primary fuel and a secondary fuel respectively. Inside the combustion chamber, the main gas flow is typically rotated to form a low velocity return gas flow zone for stabilizing the flame of the fuel combustion. In a conventional central staged combustor, secondary fuel is injected only during ignition, low operating conditions, to form an initial high temperature zone within the combustor, and to ignite the primary fuel injected after the operating conditions are raised. The secondary fuel injection hole is generally positioned at the center of the injection device, liquid fuel generates centrifugal force of high-speed tangential motion through the centrifugal nozzle to form spray and is injected towards the peripheral direction of the injection device, and the injection mode leads to the fact that secondary fuel needs to pass through main fuel airflow until reaching the vicinity of the ignition device after being injected during ignition, but the ignition system is required to be repeatedly started because of insufficient initial momentum of secondary fuel injection or too high speed of main fuel airflow, so that less fuel reaches the vicinity of the ignition device and poor flammable conditions are caused, and the ignition success rate is reduced.

Disclosure of Invention

The invention aims to solve the technical problem of improving the ignition success rate of secondary fuel of a fuel injection device of a combustion chamber of an aeroengine in the prior art, and provides the fuel injection device, the combustion chamber and the aeroengine.

The invention solves the technical problems by the following technical proposal:

a fuel injection apparatus for a combustion chamber of an aircraft engine, the fuel injection apparatus comprising:

the injection end is provided with a main fuel injection hole and a secondary fuel injection hole, the main fuel injection hole is positioned on the outer peripheral side of the secondary fuel injection hole, and the injection direction of the secondary fuel injection hole is inclined towards the outer peripheral side of the secondary fuel injection hole.

In the scheme, the main fuel injection hole of the injection end of the fuel injection device is positioned at the outer peripheral side of the secondary fuel injection hole, and the injection direction of the secondary fuel injection hole is inclined towards the outer peripheral side of the secondary fuel injection hole, so that secondary fuel injected by the secondary fuel injection hole is injected towards the main fuel injected by the main fuel injection hole and moves to the vicinity of the ignition device along with the main fuel backflow gas, the success rate of ignition of the secondary fuel is improved, and meanwhile, as the secondary fuel is obliquely injected, the diffusion range of the secondary fuel is enlarged, the secondary fuel ignition boundary is widened, and the energy requirement of an ignition system is reduced.

Preferably, the injection end comprises an injection panel, the injection panel is provided with the secondary injection hole, the primary injection hole is arranged on the outer peripheral side of the injection panel in an annular manner, and the injection direction of the secondary injection hole is inclined relative to the axial direction of the injection panel and faces the outer peripheral side of the injection panel.

In the scheme, the spraying panel has a simple structure and is convenient to process and install; each secondary fuel injection hole is positioned on the injection panel, and secondary fuel is injected from the same plane, so that uniform injection of the secondary fuel is facilitated; the main combustion stage jet hole is positioned at the peripheral side of the jet panel, so that the secondary combustion stage fuel is conveniently driven to the vicinity of the ignition device by the main combustion stage backflow gas, and the ignition success rate of the secondary combustion stage fuel is improved.

Preferably, the injection panel is provided with secondary fuel air holes, and the secondary fuel air holes are arranged on the inner peripheral side of the secondary fuel injection holes and/or the outer peripheral side of the secondary fuel injection holes.

In this scheme, secondary combustion level air hole is used for spraying secondary combustion level air, and the secondary combustion level air of secondary combustion level jet orifice of flowing through can cool down to spraying the panel, avoids high temperature flame to cause the damage to spraying the panel, prolongs the life of spraying the panel, improves fuel injection device's operational safety performance simultaneously.

Preferably, the fuel injection device further comprises a cylindrical secondary fuel injection member, an end cover of the secondary fuel injection member is provided with the injection panel, a cylindrical secondary fuel chamber is arranged in the secondary fuel injection member, secondary injection holes are communicated with the secondary fuel chamber, and a plurality of secondary injection holes are annularly distributed on the injection panel.

In the scheme, the secondary fuel chamber is cylindrical, so that secondary fuel is uniformly distributed in the secondary fuel chamber; the annular secondary fuel injection holes on the injection panel are correspondingly communicated with the cylindrical secondary fuel chamber, and secondary fuel is uniformly injected through the secondary fuel injection holes, so that the diffusion and ignition of the secondary fuel are facilitated, and secondary flame with uniform temperature is formed.

Preferably, the secondary fuel injection member includes a secondary fuel inner annular wall and a secondary fuel outer annular wall, the secondary fuel outer annular wall being provided on an outer peripheral side of the secondary fuel inner annular wall, the secondary fuel chamber being located between the secondary fuel outer annular wall and the secondary fuel inner annular wall.

In the scheme, a cylindrical secondary fuel chamber is arranged by surrounding the secondary outer annular wall and the secondary inner annular wall, and the cylindrical secondary fuel chamber is used for guiding and dispersing secondary fuel and spraying out through a secondary spraying hole.

Preferably, the injection panel is provided with a first secondary air hole and a second secondary air hole, a first secondary air chamber and a second secondary air chamber are arranged in the fuel injection device, the first secondary air chamber is communicated with the first secondary air hole, and the second secondary air chamber is communicated with the second secondary air hole;

in the radial direction of the fuel injection device, the first secondary air chamber and the secondary fuel chamber are sequentially arranged from inside to outside.

In this scheme, the interior week side and the periphery side of secondary fuel cavity are equipped with first secondary air chamber and second secondary air chamber respectively, and the second secondary air in first secondary air chamber is gone up through first secondary air hole and second secondary air hole blowout respectively to the secondary air in first secondary air chamber, and first secondary air and second secondary air can cool down to the injection panel in the blowout in-process, avoids high temperature flame to cause the damage to the injection panel.

Preferably, the fuel injection device further comprises a cylindrical main fuel injection piece, the main fuel injection piece is sleeved on the outer peripheral side of the secondary fuel injection piece, a cylindrical main fuel cavity is arranged in the main fuel injection piece, and a main fuel injection hole communicated with the main fuel cavity is arranged on the main fuel injection piece.

In the scheme, the main fuel in the main fuel cavity is sprayed out through the main fuel injection hole, the main fuel forms main fuel oil mist after being sprayed, and moves downstream along with main fuel air to evaporate and mix to form main fuel mixed gas, and the main fuel mixed gas is distributed on the outer peripheral side of secondary fuel flame in a circumferential direction to form a surrounding for the secondary fuel flame, so that the secondary fuel flame is convenient to ignite the main fuel.

Preferably, one end of the main combustion stage injection member is connected to the outer peripheral edge of the injection panel, the main combustion stage injection member comprises a main combustion stage inner annular wall and a main combustion stage outer annular wall arranged on the outer peripheral side of the main combustion stage inner annular wall, the main combustion stage fuel chamber is located between the main combustion stage outer annular wall and the main combustion stage inner annular wall, and the second secondary combustion stage air chamber is located between the main combustion stage inner annular wall and the secondary combustion stage outer annular wall.

In this scheme, the main level of combustion injection piece hoop is connected in the periphery side of injection panel, has formed the surrounding to secondary level of combustion injection piece, and the second secondary level of combustion air chamber separates main level of combustion fuel chamber and secondary level of combustion fuel chamber, and the main level of combustion fuel chamber of cylinder-type is established through main level of combustion outer rampart and main level of combustion inner rampart to enclose simultaneously, can conveniently carry out the water conservancy diversion to main level of combustion fuel to spout through main level of combustion jet orifice.

Preferably, a plurality of the secondary fuel injection holes, and/or a plurality of the first secondary fuel air holes, and/or a plurality of the second secondary fuel air holes are arranged on the injection panel in an arrangement of a plurality of rings and are uniformly distributed along the rings.

In this scheme, secondary fuel injection hole, first secondary fuel air hole and second secondary fuel air hole set up to annular range form on the injection panel for secondary fuel and secondary fuel air can diffuse the injection, select and arrange itself with the effect of having certain diffusion promptly, and evenly distributed on each ring, make things convenient for secondary fuel and air's even injection, when setting up to the multiple ring, the ring interval sets up, further increase secondary fuel's injection uniformity degree and enlarge secondary fuel's injection range, improve secondary fuel's ignition success rate, reduce secondary fuel flame temperature, reduce high temperature and arouse other pollutant emissions.

Preferably, the angle of the acute angle formed between the axis of the secondary injection hole and the axis of the injection panel is 20 ° -60 °.

In the scheme, the angle of the acute angle formed between the axis of the secondary fuel injection hole and the axis of the injection panel is 20-60 degrees, so that the injected secondary fuel has a larger diffusion range, is convenient to enter the main fuel stage backflow gas and moves to the vicinity of the ignition device along with the main fuel stage backflow gas, and is ignited by the ignition device.

Preferably, the fuel injection device further comprises a cylindrical outer cover body, the outer cover body is sleeved on the outer peripheral side of the main combustion stage injection piece, a main combustion stage air chamber is enclosed between the outer cover body and the main combustion stage injection piece, the main combustion stage injection hole is arranged along the outer peripheral side of the main combustion stage injection piece, and the opening of the main combustion stage injection hole faces and is communicated with the main combustion stage air chamber.

In the scheme, the outer cover body is sleeved on the outer peripheral side of the main combustion stage injection piece, surrounds the main combustion stage injection piece and the secondary combustion stage injection piece, and plays a role in supporting the internal structure of the main combustion stage injection piece and the secondary combustion stage injection piece; the main combustion stage air chamber is arranged between the outer cover body and the main combustion stage injection piece, the main combustion stage injection hole is communicated with the main combustion stage air chamber, and the opening faces the main combustion stage air chamber, so that main combustion stage fuel is injected towards the main combustion stage air chamber, evaporation of the main combustion stage fuel and mixing with the main combustion stage air are facilitated, a relatively uniform fuel-air mixture, namely main combustion stage mixed gas, is formed, combustion of the main combustion stage fuel is facilitated, flame temperature is reduced, and pollutant emission caused by high temperature is reduced.

Preferably, the fuel injection device further comprises a plurality of swirl vanes, and the swirl vanes are obliquely arranged in the main combustion air chamber.

In the scheme, swirl vanes obliquely arranged in the main combustion stage air chamber enable main combustion stage air in the main combustion stage air chamber to form swirl, swirl air ejected by the main combustion stage air chamber has a low-speed region and a high-speed region, a region close to the axis of the injection panel is the low-speed region, a region far away from the axis of the injection panel is the high-speed region, and the air in the low-speed region is favorable for stabilizing high-temperature flames downstream of the fuel injection device

Preferably, the fuel injection device further comprises a distributing pipe provided with a secondary fuel passage and a main fuel passage, wherein the secondary fuel passage is communicated with the secondary fuel chamber, and the main fuel passage is communicated with the main fuel chamber;

and one side of the secondary combustion stage injection piece, which is close to the main combustion stage channel, is provided with an avoidance groove, and the distribution pipe part is positioned in the avoidance groove.

In this scheme, the feeding of secondary fuel cavity and main fuel cavity is integrated in the distributing pipe, saves the space that the feed end occupy, and distributing pipe part is located the dodge inslot of secondary injection spare, and the distributing pipe stretches into fuel injection device's inside promptly, has certain supporting role to distributing pipe's link.

A combustion chamber comprising the fuel injection device described above.

In this scheme, the combustion chamber is through setting up foretell fuel injection apparatus for secondary fuel is easy to diffuse and is got into main level backward flow gas and is driven near to ignition by main level backward flow gas, has improved the success rate that secondary fuel was lighted, simultaneously because secondary fuel is by the slope injection, has enlarged secondary fuel's diffusion range, has widened secondary fuel ignition boundary, has reduced ignition system's energy demand, and can reduce secondary fuel's combustion temperature, reduces the production of high temperature pollutant.

An aeroengine comprising a combustion chamber as described above.

In this scheme, aeroengine is through setting up foretell combustion chamber for secondary fuel sprays widely, diffuses faster, has improved the success rate that secondary fuel was lighted, simultaneously because secondary fuel is by the slope injection, makes the diffusion scope of secondary fuel bigger, can reduce the temperature of the secondary flame that forms after secondary fuel ignites, improves aeroengine's working property to reduce the production of high temperature pollutant.

The invention has the positive progress effects that:

in the invention, the main fuel injection hole of the injection end of the fuel injection device is positioned at the outer peripheral side of the secondary fuel injection hole, the injection direction of the secondary fuel injection hole is inclined towards the outer peripheral side of the secondary fuel injection hole, so that secondary fuel injected by the secondary fuel injection hole is injected towards main fuel return gas and moves to the vicinity of the ignition device along with the main fuel return gas, the ignition success rate of the secondary fuel is improved, meanwhile, as the secondary fuel is obliquely injected, the diffusion range of the secondary fuel is enlarged, the ignition boundary of the secondary fuel is widened, the energy requirement of an ignition system is reduced, and the fuel injection device is suitable for most configurations and ignition modes of the existing combustion chamber adopting aviation kerosene combustion without redesigning the structure of the combustion chamber.

Drawings

Fig. 1 is a schematic perspective view of a fuel injection device according to an embodiment of the invention.

Fig. 2 is a schematic perspective view of another view of a fuel injection device according to an embodiment of the present invention.

Fig. 3 is a schematic front view of a fuel injection device according to an embodiment of the present invention.

FIG. 4 is a schematic view of the cross-section A-A in FIG. 3.

Fig. 5 is a schematic view of the cross-sectional structure B-B in fig. 4.

Fig. 6 is a schematic view of the C-C cross-sectional structure of fig. 4.

Fig. 7 is a schematic perspective view of an injection panel of a fuel injection device according to an embodiment of the present invention.

Fig. 8 is a schematic front view of an injection panel of a fuel injection device according to an embodiment of the present invention.

Fig. 9 is a schematic view of the D-D cross-sectional structure of fig. 8.

FIG. 10 is a schematic diagram of the ignition and flame combustion at low operating conditions of a fuel injection device according to an embodiment of the present invention.

FIG. 11 is a schematic diagram of flame combustion during medium-high operating conditions of a fuel injection device according to an embodiment of the present invention.

Fig. 12 is a schematic cross-sectional view of a combustion chamber according to an embodiment of the present invention.

Fig. 13 is a schematic cross-sectional view of an aeroengine according to an embodiment of the present invention.

Reference numerals illustrate:

injection end 1

Spray panel 11

Primary combustion stage injection hole 111

Secondary combustion stage injection hole 112

First secondary air hole 113

Secondary combustion stage air holes 114

Secondary combustion stage injection member 2

Secondary combustion stage fuel chamber 21

Secondary combustion stage inner annular wall 22

Secondary combustion stage outer annular wall 23

Secondary fuel end cap 24

Avoidance groove 25

First secondary air chamber 3

Second stage combustion air chamber 4

Main combustion stage injection piece 5

Main combustion stage fuel chamber 51

Main combustion stage inner annular wall 52

Main combustion stage outer annular wall 53

Main fuel end cap 54

Outer cover 6

Primary combustion stage air chamber 7

Swirl vane 8

Distribution pipe 9

Secondary combustion stage channel 91

Main combustion stage path 92

Combustion chamber 100

Fuel injection device 101

Flame tube 102

Ignition device 103

Aero-engine 200

Main combustion grade fuel 301

Main fuel grade oil mist 3011

Secondary fuel 302

Primary combustion stage air 303

Secondary combustion stage air 304

First secondary air 3041

Secondary combustion stage air 3042

Spark 305

Primary combustion stage return gas 306

Secondary combustion stage flame 307

First high temperature zone 308

Primary combustion stage mixed gas 309

Second high temperature region 310

Main combustion stage feed pipe 311

Secondary combustion stage feed pipe 312

Detailed Description

The invention will now be more fully described by way of example only and with reference to the accompanying drawings, but the invention is not thereby limited to the embodiments described.

As shown in fig. 1 to 11, the present embodiment provides a fuel injection device 101, the fuel injection device 101 being used for a combustion chamber 100 of an aircraft engine 200, the fuel injection device 101 including an injection port 1, the injection port 1 being provided with a main fuel injection hole 111 and a secondary fuel injection hole 112, the main fuel injection hole 111 being located on an outer peripheral side of the secondary fuel injection hole 112, an injection direction of the secondary fuel injection hole 112 being inclined toward the outer peripheral side of the fuel injection device 101. The above structure makes the secondary fuel 302 injected from the secondary injection hole 112 to be injected towards the main fuel return gas 306 and move to the vicinity of the ignition device 103 along with the main fuel return gas 306, so as to improve the ignition success rate of the secondary fuel 302, and simultaneously, because the secondary fuel 302 is obliquely injected, the diffusion range of the secondary fuel 302 is enlarged, the secondary ignition boundary is widened, the energy requirement of the ignition system is reduced, and the fuel injection device 101 is suitable for most configurations and ignition modes of the existing combustion chamber 100 adopting aviation kerosene combustion, without redesigning the structure of the combustion chamber 100.

In the present embodiment, the injection port 1 includes the injection panel 11, the injection panel 11 is provided with the secondary injection holes 112, the primary injection holes 111 are provided around the outer peripheral side of the injection panel 11, and the injection direction of the secondary injection holes 112 is inclined with respect to the axial direction of the injection panel 11 and directed toward the outer peripheral side of the injection panel 11. The spraying panel 11 has a simple structure and is convenient to process and install; each secondary fuel injection hole 112 is positioned on the injection panel 11, and secondary fuel 302 is injected from the same plane, so that uniform injection of the secondary fuel 302 is facilitated; the primary injection hole 111 is located at the outer peripheral side of the injection panel 11, so that the secondary fuel 302 is conveniently driven to the vicinity of the ignition device 103 by the primary return gas 306, and the ignition success rate of the secondary fuel 302 is improved.

In the present embodiment, the injection panel 11 is provided with secondary fuel air holes provided on the inner peripheral side of the secondary fuel injection holes 112 and the outer peripheral side of the secondary fuel injection holes 112. The secondary fuel air holes are used for injecting secondary fuel air 304, and the secondary fuel air 304 flowing through the secondary fuel injection holes 112 can cool the injection panel 11, so that the damage of high-temperature flame to the injection panel 11 is avoided, the service life of the injection panel 11 is prolonged, and the working safety performance of the fuel injection device 101 is improved. Specifically, in the present embodiment, the secondary fuel air holes include a first secondary fuel air hole 113 provided on the inner peripheral side of the secondary fuel injection hole 112 and a second secondary fuel air hole 114 provided on the outer peripheral side of the secondary fuel injection hole 112. In other alternative embodiments, the injection panel 11 may be provided with only the first secondary air holes 113 or only the second secondary air holes 114.

In this embodiment, the fuel injection device 101 further includes a cylindrical secondary fuel injection member 2, an end cover of the secondary fuel injection member 2 is provided with an injection panel 11, a cylindrical secondary fuel chamber 21 is provided in the secondary fuel injection member 2, secondary injection holes 112 are communicated with the secondary fuel chamber 21, and a plurality of secondary injection holes 112 are annularly distributed on the injection panel 11. The secondary fuel chamber 21 is cylindrical, so that secondary fuel 302 is uniformly distributed in the secondary fuel chamber 21; the annular secondary fuel injection holes 112 on the injection panel 11 are correspondingly communicated with the cylindrical secondary fuel chamber 21, and the secondary fuel 302 is uniformly injected through the secondary fuel injection holes 112, so that the diffusion and ignition of the secondary fuel 302 are facilitated, and a secondary flame 307 with a relatively uniform temperature is formed.

In the present embodiment, the secondary injection member 2 includes a secondary inner annular wall 22 and a secondary outer annular wall 23, the secondary outer annular wall 23 being provided on the outer peripheral side of the secondary inner annular wall, and the secondary fuel chamber 21 being located between the secondary outer annular wall 23 and the secondary inner annular wall 22. The secondary fuel chamber 21 is formed by enclosing the secondary outer annular wall 23 and the secondary inner annular wall 22, and the secondary fuel 302 is guided and dispersed by the secondary fuel chamber 21 and is ejected through the secondary injection holes 112. Specifically, in the present embodiment, the secondary fuel injection member 2 further includes a secondary end cover 24, the secondary end cover 24 covers one end of the secondary inner annular wall 22 and the secondary outer annular wall 23, the injection panel 11 covers the other end of the secondary inner annular wall 22 and the secondary outer annular wall 23, and the secondary end cover 24, the secondary inner annular wall 22, the secondary outer annular wall 23 and the injection panel 11 together enclose a secondary fuel chamber 21. Further, as shown in fig. 7 and 9, in the present embodiment, the injection panel 11 is integrally formed with the secondary inner annular wall 22 and a portion of the secondary outer annular wall 23, and in other alternative embodiments, the injection panel 11 may be separately manufactured and then connected to the secondary injection member 2.

In the present embodiment, the injection panel 11 is provided with a first secondary air hole 113 and a second secondary air hole 114, the fuel injection device 101 is internally provided with a first secondary air chamber 3 and a second secondary air chamber 4, the first secondary air chamber 3 is communicated with the first secondary air hole 113, and the second secondary air chamber 4 is communicated with the second secondary air hole 114; in the radial direction of the fuel injection device 101, the first secondary air chamber 3, the secondary fuel chamber 21, and the second secondary air chamber 4 are arranged in this order from the inside to the outside. The inner peripheral side and the outer peripheral side of the secondary combustion stage fuel chamber 21 are respectively provided with a first secondary combustion stage air chamber 3 and a second secondary combustion stage air chamber 4, and the first secondary combustion stage air 3041 in the first secondary combustion stage air chamber 3 and the second secondary combustion stage air 3042 in the second secondary combustion stage air chamber 4 are respectively sprayed out through the first secondary combustion stage air holes 113 and the second secondary combustion stage air holes 114, so that the first secondary combustion stage air 3041 and the second secondary combustion stage air 3042 can cool the spray panel 11 in the spraying process, and the damage of high-temperature flame to the spray panel 11 is avoided.

In this embodiment, the fuel injection device 101 further includes a cylindrical main fuel injection member 5, the main fuel injection member 5 is sleeved on the outer peripheral side of the secondary fuel injection member 2, a cylindrical main fuel chamber 51 is disposed in the main fuel injection member 5, and the main fuel injection member 5 is provided with a main fuel injection hole 111 communicating with the main fuel chamber 51. The main fuel 301 in the main fuel chamber 51 is sprayed out through the main fuel spray hole 111, the main fuel 301 forms main fuel oil mist 3011 after being sprayed, and moves downstream along with the main fuel air 303 to evaporate and mix to form main fuel mixed gas 309, and the main fuel mixed gas is distributed on the outer periphery side of the secondary fuel flame 307 in a circumferential direction to form a surrounding for the secondary fuel flame, so that the secondary fuel flame is convenient to ignite the main fuel 301. Specifically, in the present embodiment, the main stage injection holes 111 are located axially upstream of the injection panel 11 and radially outward of the injection panel 11 to allow space and time for the evaporated, mixed forming main stage mixture 309 of the main stage fuel 301 after injection.

In the present embodiment, one end of the main stage injection piece 5 is connected to the outer peripheral edge of the injection panel 11, the main stage injection piece 5 includes a main stage inner annular wall 52 and a main stage outer annular wall 53 provided on the outer peripheral side of the main stage inner annular wall 52, the main stage fuel chamber 51 is located between the main stage outer annular wall 53 and the main stage inner annular wall 52, and the second secondary stage air chamber 4 is located between the main stage inner annular wall 52 and the secondary stage outer annular wall 23. The main fuel injection piece 5 is connected to the outer peripheral side of the injection panel 11 in a circumferential direction, so that a surrounding is formed on the secondary fuel injection piece 2, the main fuel cavity 51 and the secondary fuel cavity 21 are separated by the secondary fuel air cavity 4, and meanwhile, the main fuel cavity 51 in a cylindrical shape is surrounded by the main fuel outer annular wall 53 and the main fuel inner annular wall 52, so that the main fuel 301 can be conveniently guided, and is sprayed out through the main fuel injection hole 111. Specifically, in the present embodiment, the main fuel stage injection member 5 further includes a main fuel stage end cover 54, and the main fuel stage end cover 54 covers one end of the main fuel stage inner annular wall 52 and the main fuel stage outer annular wall 53, and the main fuel stage end cover 54, the main fuel stage inner annular wall 52, and the main fuel stage outer annular wall 53 together enclose the main fuel stage fuel chamber 51.

In the present embodiment, the plurality of secondary injection holes 112, the plurality of first secondary air holes 113 and the plurality of second secondary air holes 114 are all disposed on the injection panel 11 in a plurality of rings arranged in a uniform distribution along the rings. Specifically, as shown in fig. 8, the plurality of secondary injection holes 112 in the present embodiment are provided with one ring, and the plurality of first secondary air holes 113 and the plurality of second secondary air holes 114 are provided with three rings, respectively. The secondary fuel injection holes 112, the first secondary fuel air holes 113 and the second secondary fuel air holes 114 are arranged in an annular arrangement form on the injection panel 11, so that the secondary fuel 302 and the secondary fuel air 304 can be subjected to diffusion injection, namely, the selection and arrangement of injection points have a certain diffusion effect, and are uniformly distributed on each ring, so that the secondary fuel 302 and the secondary fuel air 304 can be conveniently uniformly injected, when the secondary fuel injection holes are arranged in multiple rings, the rings are arranged at intervals, the injection uniformity of the secondary fuel 302 is further increased, the injection range of the secondary fuel 302 is enlarged, the ignition success rate of the secondary fuel 302 is improved, the secondary flame temperature is reduced, and the generation of high-temperature pollutants is reduced. In other alternative embodiments, the number and specific arrangement of the plurality of secondary fuel injection holes 112, the plurality of first secondary fuel air holes 113, and the plurality of second secondary fuel air holes 114 is not limited to this embodiment.

In the present embodiment, the second secondary air holes 114 are inclined toward the outer peripheral side of the injection panel 11, and the angle at which the second secondary air holes 114 are inclined toward the outer peripheral side of the injection panel 11 is smaller than the angle at which the secondary injection holes 112 are inclined toward the outer peripheral side of the injection panel 11. Specifically, as shown in fig. 9, θ is an angle at which the secondary injection holes 112 are inclined toward the outer peripheral side of the injection panel 11, and the value of θ may be selected according to factors such as the intensity of the primary return gas 306, the height of the liner 102 in the combustion chamber 100, and the position of the ignition device 103. The second secondary air hole 114 is disposed around the outer circumference of the secondary injection hole 112, and the inclination angle of the second secondary air hole 114 is smaller than that of the secondary injection hole 112, so that the secondary fuel 302 injected from the secondary injection hole 112 is injected toward the second secondary air 3042 injected from the second secondary air hole 114, and the secondary fuel 302 and the second secondary air 3042 are conveniently mixed.

In the present embodiment, the angle of the acute angle formed between the axis of the secondary injection hole 112 and the axis of the injection panel 11 is 20 ° -60 °. The injected secondary fuel 302 has a larger diffusion range, and conveniently enters the main fuel stage backflow gas 306 and moves to the vicinity of the ignition device 103 along with the main fuel stage backflow gas 306, so that the secondary fuel is ignited by the ignition device 103.

In this embodiment, the fuel injection device 101 further includes a cylindrical outer housing 6, the outer housing 6 is sleeved on the outer peripheral side of the main fuel injection member 5, a main fuel air chamber 7 is enclosed between the outer housing 6 and the main fuel injection member 5, the main fuel injection hole 111 is disposed along the outer peripheral side of the main fuel injection member 5, and the opening of the main fuel injection hole 111 faces and is communicated with the main fuel air chamber 7. The outer cover 6 is sleeved on the outer periphery side of the main combustion stage injection piece 5, surrounds the main combustion stage injection piece 5 and the secondary combustion stage injection piece 2, and plays a role in supporting the internal structure of the main combustion stage injection piece; the main combustion stage air chamber 7 is arranged between the outer cover 6 and the main combustion stage injection piece 5, the main combustion stage injection hole 111 is communicated with the main combustion stage air chamber 7, and the opening faces the main combustion stage air chamber 7, so that main combustion stage fuel 301 is injected towards the main combustion stage air chamber 7, evaporation of the main combustion stage fuel 301 is facilitated, the main combustion stage fuel is mixed with the main combustion stage air 303, a relatively uniform fuel-air mixture, namely main combustion stage mixed gas 309, is formed, combustion of the main combustion stage fuel 301 is facilitated, flame temperature is reduced, and generation and emission of high-temperature pollutants are reduced.

In the present embodiment, the fuel injection device 101 further includes a plurality of swirl vanes 8, and the swirl vanes 8 are disposed obliquely in the main combustion stage air chamber 7. Swirl vanes 8 are obliquely arranged in the main combustion stage air chamber 7 to enable the main combustion stage air 303 in the main combustion stage air chamber 7 to form swirl, swirl air ejected by the main combustion stage air chamber 7 has a low-speed region and a high-speed region, a region close to the axis of the injection panel 11 is the low-speed region, a region far away from the axis of the injection panel 11 is the high-speed region, and the air in the low-speed region is favorable for stabilizing high-temperature flames downstream of the fuel injection device 101.

In the present embodiment, the fuel injection device 101 further includes a distribution pipe 9, the distribution pipe 9 is provided with a secondary fuel stage passage 91 and a primary fuel stage passage 92, the secondary fuel stage passage 91 communicates with the secondary fuel stage chamber 21, and the primary fuel stage passage 92 communicates with the primary fuel stage chamber 51; the side of the secondary fuel injection member 2, which is close to the primary fuel channel 92, is provided with a relief groove 25, and the distribution pipe 9 is partially positioned in the relief groove 25. The feeding of secondary fuel cavity 21 and main fuel cavity 51 is integrated in distributing pipe 9, saves the space that the feed end occupy, and distributing pipe 9 part is located the dodge inslot 25 of secondary fuel injection member 2, and distributing pipe 9 stretches into the inside of fuel injection apparatus 101 promptly, and the link of distributing pipe 9 and main fuel injection member 5 and the link of distributing pipe 9 and secondary fuel injection member 2 all have certain supporting role.

In this embodiment, the fuel injection device 101 further includes a main fuel feed pipe 311 and a secondary fuel feed pipe 312, the main fuel feed pipe 311 is connected to the main fuel channel 92 of the distribution pipe 9, the secondary fuel feed pipe 312 is connected to the secondary fuel channel 91 of the distribution pipe 9, and the main fuel feed pipe 311 and the secondary fuel feed pipe 312 are both partially surrounded by the main fuel injector 5 and the secondary fuel injector 2, so that the connection ends of the main fuel feed pipe 311 and the distribution pipe 9 and the connection ends of the secondary fuel feed pipe 312 and the distribution pipe 9 have a certain supporting effect.

As shown in fig. 12, the present embodiment also provides a combustion chamber 100, the combustion chamber 100 including the fuel injection device 101 described above. By arranging the fuel injection device 101 in the combustion chamber 100, the secondary fuel 302 is easy to diffuse into the main fuel return gas 306 and is driven to the vicinity of the ignition device 103 by the main fuel return gas 306, so that the ignition success rate of the secondary fuel 302 is improved, meanwhile, as the secondary fuel 302 is obliquely injected, the diffusion range of the secondary fuel 302 is enlarged, the secondary ignition boundary is widened, the energy requirement of an ignition system is reduced, the temperature of secondary flame 307 formed after the secondary fuel 302 is ignited can be reduced, and the generation of high-temperature pollutants is reduced.

In this embodiment, the combustion chamber 100 further includes a flame tube 102 and an ignition device 103, the fuel injection device 101 is disposed at one end of the flame tube 102, and the ignition device 103 is disposed downstream of the fuel injection device 101 and is disposed on a side wall of the flame tube 102; the cross-sectional area of the flame tube 102 gradually decreases in the injection direction of the fuel injection device 101. In the downstream direction of the fuel injection device 101, the cross-sectional area of the flame tube 102 gradually decreases. When the aeroengine operating condition increases, the main fuel 301 starts to be injected (at this time, the secondary fuel 302 is already ignited), and the main fuel mixed gas 309 (i.e. the mixed gas formed by the main fuel 301 after being evaporated and mixed in the main fuel air 303) injected by the fuel injection device 101 moves downstream, so that the secondary flame wrapped by the main fuel moves to ignite, forming a larger main stable flame, and the secondary flame 307 is also wrapped in.

In this embodiment, the secondary fuel 302 is hydrogen, and the main fuel 301 is aviation kerosene. The fuel injection device 101 operates as follows:

referring to FIG. 10 in combination with FIG. 12, combustion is performed using secondary fuel 302 only when combustion chamber 100 is in an ignition or lower operating condition. Specifically, when the aeroengine 200 is in the ignition condition, only the secondary injection hole 112 in the combustion chamber 100 injects the secondary fuel 302, that is, the hydrogen fuel, toward the outer peripheral side thereof, the secondary fuel 302 diffuses into the main combustion stage return gas 306 after being injected and is driven to the vicinity of the ignition device 103, the secondary fuel is ignited by the electric spark 305 of the ignition device 103 to form high-temperature fuel gas (the ignition device 103 stops working after successful ignition of the secondary fuel), part of the high-temperature fuel gas flows back to the vicinity of the secondary injection hole 112 along with the main combustion stage return gas 306 (at this time, the main combustion stage return gas 306 mainly comprises the main combustion stage air 303 and the secondary fuel 302), and the newly injected secondary fuel 302 is ignited, so that the secondary fuel 302 forms a stable secondary combustion stage flame 307 and a first high-temperature region 308 after injection. When the operation condition of the aeroengine 200 is raised but still in a small operation condition, only the secondary fuel injection hole 112 still injects the secondary fuel 302, namely hydrogen fuel, but the flow of the secondary fuel hydrogen fuel 302 is continuously increased, and the newly-entered secondary fuel hydrogen fuel 302 is ignited by the secondary flame 307 or the secondary high-temperature zone 308 downstream of the fuel injection device 101, so that the area of the secondary flame 307 or the secondary high-temperature zone 308 is continuously enlarged.

Referring to FIG. 11 in combination with FIG. 12, when the combustion chamber 100 is at a higher operating condition, the injection of the primary fuel 301 is increased while the secondary fuel 302 is being injected (where ignition has been performed, the secondary fuel 302 is in a combustion state, and a secondary flame 307 has been generated). The main fuel 301 is ejected through the main injection holes 111 to form a main fuel oil mist 3011, and the main fuel oil mist 3011 evaporates in the main fuel air chamber 7 and is mixed with the main fuel air 303 to form a main fuel mixture 309. The primary mixed gas 309 is wrapped around the outer circumference of the secondary flame and is ignited by the secondary flame 307, forming a second high temperature zone 310, and continuously igniting the newly entered primary mixed gas 309, so as to realize stable combustion of the primary fuel 301. Because the main combustion stage fuel 301 adopts a pre-mixing and pre-evaporating combustion mode, the temperature of the main combustion stage fuel 301 during combustion can be reduced, and thus, the generation of high-temperature pollutants is reduced.

In the present embodiment, the injection direction of the hydrogen gas is inclined toward the outer periphery of the secondary injection hole 112, and the hydrogen gas itself has strong diffusivity, so that the hydrogen gas more easily reaches the vicinity of the ignition device 103 with the main stage return gas 306 to be ignited, and the configuration and the ignition manner of the existing combustion chamber 100 which mostly adopts aviation kerosene combustion can be adapted without having to redesign the structure of the combustion chamber 100.

In addition, the use of hydrogen for secondary fuel 302 has the following beneficial effects: the hydrogen is mainly used for realizing ignition and combustion under low working conditions, the hydrogen fuel consumption is small, complex pipeline support is not needed (if the hydrogen consumption is large, additional pipeline design is needed because the performances of the hydrogen and aviation kerosene are greatly different), and the fuel injection device 101 of the combustion chamber 100 of the existing aeroengine 200 is suitable for improvement; the hydrogen is easy to ignite, the required ignition energy is low, and the load of the ignition device 103 can be reduced; the characteristics of low ignition energy and high flame propagation speed of the hydrogen can obviously improve the ignition performance of the combustion chamber 100, so as to widen the ignition boundary, in particular to high altitude and high origin ignition performance; the combustion product of the hydrogen is basically water, so that the carbon emission can be reduced, and the energy conservation and environmental protection are realized.

As shown in fig. 13, the present embodiment further provides an aero-engine 200, and the aero-engine 200 includes the combustion chamber 100 described above. By arranging the combustion chamber 100, the aero-engine 200 ensures that the secondary fuel 302 is wider in injection spread and quicker in diffusion, improves the ignition success rate of the secondary fuel 302, simultaneously ensures that the diffusion range of the secondary fuel 302 is wider because the secondary fuel 302 is obliquely injected, can reduce the combustion temperature of the secondary fuel 302, improves the working performance of the aero-engine 200 and reduces the generation of high-temperature pollutants.

While specific embodiments of the invention have been described above, it will be appreciated by those skilled in the art that this is by way of example only, and the scope of the invention is defined by the appended claims. Various changes and modifications to these embodiments may be made by those skilled in the art without departing from the principles and spirit of the invention, but such changes and modifications fall within the scope of the invention.

Claims (15)

1. A fuel injection device for a combustion chamber of an aircraft engine, the fuel injection device comprising:

the injection end is provided with a main fuel injection hole and a secondary fuel injection hole, the main fuel injection hole is positioned on the outer peripheral side of the secondary fuel injection hole, and the injection direction of the secondary fuel injection hole is inclined towards the outer peripheral side of the secondary fuel injection hole.

2. The fuel injection device according to claim 1, wherein the injection end includes an injection panel on which the secondary injection hole is provided, the primary injection hole being provided on an outer peripheral side of the injection panel, and an injection direction of the secondary injection hole being inclined with respect to an axial direction of the injection panel and directed toward the outer peripheral side of the injection panel.

3. The fuel injection device according to claim 2, wherein secondary fuel air holes are provided in the injection panel, the secondary fuel air holes being provided on an inner peripheral side of the secondary fuel injection holes and/or an outer peripheral side of the secondary fuel injection holes.

4. The fuel injection device of claim 2, further comprising a cylindrical secondary injection member having an end cap with the injection panel, a cylindrical secondary fuel chamber disposed within the secondary injection member, the secondary injection holes communicating with the secondary fuel chamber, the plurality of secondary injection holes being annularly distributed on the injection panel.

5. The fuel injection apparatus of claim 4 wherein said secondary injection member comprises a secondary inner annular wall and a secondary outer annular wall, said secondary outer annular wall being disposed on an outer peripheral side of said secondary inner annular wall, said secondary fuel chamber being located between said secondary outer annular wall and said secondary inner annular wall.

6. The fuel injection device of claim 5 wherein the injection panel is provided with a first secondary air orifice and a second secondary air orifice, the fuel injection device being provided with a first secondary air chamber and a second secondary air chamber therein, the first secondary air chamber being in communication with the first secondary air orifice and the second secondary air chamber being in communication with the second secondary air orifice;

in the radial direction of the fuel injection device, the first secondary air chamber and the secondary fuel chamber are sequentially arranged from inside to outside.

7. The fuel injection device of claim 6, further comprising a cylindrical primary fuel injection member, wherein the primary fuel injection member is disposed around the secondary fuel injection member, wherein a cylindrical primary fuel chamber is disposed in the primary fuel injection member, and wherein the primary fuel injection member is provided with a primary injection hole communicating with the primary fuel chamber.

8. The fuel injection apparatus of claim 7 wherein one end of said main stage injection member is connected to the peripheral edge of said injection panel, said main stage injection member comprising a main stage inner annular wall and a main stage outer annular wall disposed on the peripheral side of said main stage inner annular wall, said main stage fuel chamber being located between said main stage outer annular wall and said main stage inner annular wall, said secondary stage air chamber being located between said main stage inner annular wall and said secondary stage outer annular wall.

9. The fuel injection apparatus of claim 8 wherein a plurality of said secondary fuel injection holes and/or a plurality of said primary secondary fuel air holes and/or a plurality of said secondary fuel air holes are each disposed in an array of rings on said injection panel and are evenly distributed along the ring.

10. The fuel injection device of claim 2, wherein an angle of an acute angle formed between an axis of the secondary injection hole and an axis of the injection panel is 20 ° -60 °.

11. The fuel injection device of claim 7, further comprising a cylindrical outer housing, wherein the outer housing is disposed around the outer periphery of the primary fuel stage injection member, a primary fuel stage air chamber is defined between the outer housing and the primary fuel stage injection member, the primary fuel stage injection hole is disposed along the outer periphery of the primary fuel stage injection member, and the primary fuel stage injection hole is open toward and in communication with the primary fuel stage air chamber.

12. The fuel injection device of claim 11, further comprising a plurality of swirl vanes disposed obliquely within the main combustion stage air chamber.

13. The fuel injection device of claim 7, further comprising a distribution pipe provided with a secondary fuel passage and a primary fuel passage, the secondary fuel passage communicating with the secondary fuel chamber, the primary fuel passage communicating with the primary fuel chamber;

and one side of the secondary combustion stage injection piece, which is close to the main combustion stage channel, is provided with an avoidance groove, and the distribution pipe part is positioned in the avoidance groove.

14. A combustion chamber, characterized in that it comprises a fuel injection device according to any one of claims 1-13.

15. An aircraft engine, characterized in that it comprises a combustion chamber according to claim 14.